from libs import *
from OpenGL.GL import shaders
import os

VS = f"""
#version 120
{"\n".join([f"attribute {a};" for a in VERTEX_ATTRS])}
{"\n".join([f"varying {a}F;" for a in VERTEX_ATTRS])}
{"\n".join([
    f"uniform {v[1]} {k};" for (k, v) in UNIFORMS.items() if v[0] == "vert"
])}
void main() {{
    gl_Position = MVP * vec4(position, 1.0);
{"\n".join([f"    {a.split()[1]}F = {a.split()[1]};" for a in VERTEX_ATTRS])}
}}
"""

FS = f"""
#version 120
{"\n".join([f"varying {a}F;" for a in VERTEX_ATTRS])}
{"\n".join([
    f"uniform {v[1]} {k};" for (k, v) in UNIFORMS.items() if v[0] == "frag"
])}
void main() {{
    float ambient = reflsF.x;
    vec3 lightDir = normalize(lightPos.xyz - positionF);
    float diffuse = reflsF.y * lightPos.w *
        dot(normalF, lightDir) / pow(distance(lightPos.xyz, positionF), 2);
    float specular = reflsF.z * lightPos.w * pow(max(dot(
        normalize(camPos - positionF), reflect(-lightDir, normalF)
    ), 0.0), reflsF.w);
    float j = texcF.z;
    vec3 c = colF.xyz;
    if (abs(j) < 1e-3)
        c = texture2D(tex[0], texcF.xy).xyz;
    if (abs(j - 1.0) < 1e-3)
        c = texture2D(tex[1], texcF.xy).xyz;
    gl_FragColor = vec4((ambient + diffuse + specular) * c, colF.w);
}}
"""

def load_texture(i, fname):
    pli = pygame.image.load(fname).convert()
    (tw, th) = pli.get_size()
    img_data = np.array(list(pygame.image.tobytes(pli, "RGB")), np.uint8)
    tex = glGenTextures(1)
    glActiveTexture(GL_TEXTURE0 + i)
    glBindTexture(GL_TEXTURE_2D, tex)
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR)
    glTexImage2D(
        GL_TEXTURE_2D, 0, GL_RGB, tw, th,
        0, GL_RGB, GL_UNSIGNED_BYTE, img_data
    )

def init_display():
    pygame.init()
    full = os.environ.get("FULLSCREEN")
    pygame.display.set_mode((640, 480),
        pygame.DOUBLEBUF | pygame.OPENGL |
        (pygame.FULLSCREEN | pygame.SCALED if full else pygame.RESIZABLE),
    vsync=1)
    pygame.event.set_allowed([
        pygame.KEYDOWN, pygame.KEYUP,
        pygame.MOUSEBUTTONDOWN, pygame.MOUSEBUTTONUP, pygame.MOUSEMOTION,
        pygame.QUIT, pygame.WINDOWRESIZED, pygame.WINDOWSIZECHANGED
    ])
    pygame.display.set_caption("Voxels")
    load_texture(0, "favicon.png")
    load_texture(1, "container.jpg")
    sp = shaders.compileProgram(
        shaders.compileShader(VS, GL_VERTEX_SHADER),
        shaders.compileShader(FS, GL_FRAGMENT_SHADER)
    )
    for (k, v) in UNIFORMS.items():
        v[2] = glGetUniformLocation(sp, k)
    glUseProgram(sp)
    glUniform1iv(UNIFORMS["tex"][2], 2, np.array([0, 1]))
    glEnable(GL_DEPTH_TEST)
    glEnable(GL_BLEND)
    glEnable(GL_CULL_FACE)
    glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA)
    glClearColor(0.1, 0.1, 0.1, 1.0)